Radio communication system, radio communication apparatus, and radio communicating method

ABSTRACT

A mobile station capable of connected to an information providing server via a radio link, comprises a reception history table which stores an identification of information which has been received, and a controller which prevents the same information from being received based on the identification in the reception history table.

TECHNICAL FIELD

[0001] The present invention relates to a short distance radiocommunication system, particularly to a radio communication system andradio communicating method realizing power saving of a radiocommunication apparatus.

BACKGROUND ART

[0002] In recent years, a short distance radio interface calledBluetooth has been developed in which a 2.45 GHz Industrial ScientificMedical (ISM) band is used as a carrier wave frequency, and variousmobile apparatuses such as cellular phones, notebook-size personalcomputers, digital still cameras, and mobile game machines can beconnected by radio.

[0003] In a radio communication system including such an interface, thesame information is repeatedly transmitted in the same frequency band insome cases. When the cellular phone is used as a mobile radio apparatus,the cellular phone is constantly waiting for reception. Even wheninformation has the same content as that of the already receivedinformation, the information is repeatedly received. Therefore, there isa problem that power consumption during reception increases and abattery is remarkably consumed. For example, while a user waits forsomeone in front of a station ticket gate, a train timetable, a faretable, and the like are repeatedly transmitted, such information isrepeatedly received by a mobile terminal, and power is consumed duringwaiting. To prevent this problem, the user has to temporarily turn off apower supply of radio communication. However, with the cellular phone,when the power supply is turned off, an inherent function of thecellular phone is hindered. Therefore, this is not a realistic solution.

[0004] Moreover, since the same information is repeatedly transmitted,the radio terminal has no memory for storing the received information.Therefore, the already received portion of information cannot beconfirmed. When a video/music program is transmitted in real time, andif the user starts browsing the information from a midway timing of theprogram, a first part of the program cannot be seen until the nexttransmission of the program.

[0005] On the other hand, a technique associated with power saving ofthe radio apparatus is disclosed in Japanese Patent Disclosure (KOKAI)No. 10-32504. This discloses a technique of judging an influence ofnoise or the like in an early stage, preventing a received current fromincreasing, and realizing the power saving. That is, if a time for whichreception strength indicates a determined value or a smaller valuecontinues for not less than a predetermined time, it can be determinedthat a received signal includes a noise and therefore a normal signalcannot be received. Thus, the reception is stopped. In this method,however, the same repeatedly transmitted information cannot be preventedfrom being received many times.

[0006] As described above, in the radio communication system using theconventional short distance radio interface, when the radiocommunication is performed in the same frequency band, a receivingapparatus constantly receives transmitted information. Therefore, evenif the same information is received, the power consumption duringreception increases, and the battery is remarkably consumed.

[0007] Moreover, when video or sound information is received in realtime, the memory for storing the information being received is notprovided. The information is browsed from halfway depending upon abrowsing start timing. Therefore, it cannot be guaranteed that theinformation is transmitted to the user from the beginning.

DISCLOSURE OF INVENTION

[0008] The present invention is directed to method and apparatus thatsubstantially obviates one or more of the problems due to limitationsand disadvantages of the related art.

[0009] According to one aspect of the present invention, a radiocommunication apparatus comprises a reception history table configuredto store information-identification identifying information which hasbeen received; and a controller configured to prevent information frombeing received of which information-identification is stored in thereception history table.

[0010] According to another aspect of the present invention, a radiocommunication apparatus comprises a transmission history tableconfigured to store information-identification identifying informationwhich has been transmitted; and a controller configured to preventinformation from being transmitted of which information-identificationis stored in the transmission history table.

BRIEF DESCRIPTION OF DRAWINGS

[0011] The accompanying drawings, which are incorporated in andconstitute a part of the specification, illustrate presently embodimentsof the present invention and, together with the general descriptiongiven above and the detailed description of the embodiments given below,serve to explain the principles of the present invention in which:

[0012]FIG. 1 is a diagram showing a Bluetooth communication networkmodel;

[0013]FIG. 2 is a diagram showing the whole radio communication systemaccording to one embodiment of the present invention;

[0014]FIG. 3 is a schematic diagram showing a basic configuration of aninformation providing server for use in the radio communication systemaccording to the embodiment of the present invention;

[0015]FIG. 4 is a block diagram showing a hardware configuration of aninformation providing server shown in FIG. 2;

[0016]FIG. 5 is a block diagram showing a software configuration of theinformation providing server shown in FIG. 2;

[0017]FIG. 6 is a block diagram showing a hardware configuration of apotable terminal shown in FIG. 2;

[0018]FIG. 7 is a block diagram showing a software configuration of thepotable terminal shown in FIG. 2;

[0019]FIG. 8 is a diagram showing one example of a history managementtable of the information providing server and mobile terminal;

[0020]FIG. 9 is a diagram showing a location at which actual contentsare stored and which is indicated by a contents pointer of the historymanagement table shown in FIG. 8;

[0021]FIG. 10 is a flowchart showing a processing of using the 2.45 GHzband radio communication to connect the information providing server tothe mobile terminal, and preventing the information providing serverfrom repeatedly transmitting the same information to the mobileterminal;

[0022]FIG. 11 is a flowchart showing a processing of using the 2.45 GHzband radio communication to connect the mobile terminal to theinformation providing server, and preventing the mobile terminal fromrepeatedly receiving the same information from the information providingserver;

[0023]FIG. 12 is a flowchart showing a processing on an informationproviding server side, in which the information providing serverbroadcasts the information in a second embodiment;

[0024]FIG. 13 is a diagram showing another example of the historymanagement table in a third embodiment;

[0025]FIG. 14 is a diagram showing a processing for preventing theinformation providing server from repeatedly transmitting the sameinformation to the mobile terminal in a fourth embodiment; and

[0026]FIG. 15 is a diagram showing a modification example of theembodiment shown in FIG. 14.

BEST MODE FOR CARRYING OUT OF THE INVENTION

[0027] Embodiments of the present invention will be describedhereinafter with reference to the drawings.

[0028] In the embodiments, an example of a communication system by aBluetooth interface will be described. FIG. 1 is a network configurationdiagram showing a Bluetooth communication model. In communication of oneapparatus with the Bluetooth interface mounted thereon with amultiplicity of apparatuses, the communication apparatuses areclassified into master and slave. One master and seven slaves at maximumconstitute a network called Piconet. The master can communicatesimultaneously with seven slaves at maximum. A network formed byconnecting plural Piconets is called Scatternet.

[0029]FIG. 2 shows the whole configuration of the radio communicationsystem according to the present embodiment.

[0030] A mobile station 2 corresponding to the slave in FIG. 1 (here acellular phone is described as an example, but the mobile station is notlimited to the cellular phone, and may be a mobile personal computer orthe like, or constituted of different types of mobile apparatuses) usesradio waves, for example, of the 800 MHz band to transmit/receive soundor data with respect to a base station (cellular phone base station) 3installed in each district. The base station 3 constitutes apredetermined radio zone called a service area, and realizescommunication with the cellular phone 2 in the radio zone. The basestation 3 is connected to a server 5 via a public switched telephonenetwork 4. The cellular phone 2 can also be used with a head set 6 fortalking.

[0031] The cellular phone 2 is equipped with not only a radiocommunication interface for transmitting/receiving radio waves of the800 MHz band to/from the base station 3, but also a radio communicationinterface for transmitting/receiving radio waves of the 2.45 GHz bandto/from a personal computer 1. The cellular phone 2 includes an LCD 2 afor displaying data, a keyboard 2 b for inputting the data, and thelike.

[0032] An information providing server corresponding to the master inFIG. 1 (here the personal computer 1 is described as an example, but theserver is not limited to the personal computer, and may be a mobilepersonal computer or the like, or the same type of apparatus as theslave) is connected to the cellular phone 2 via radio waves of aspecific frequency band which differs from radio waves for use in acellular phone system. Concretely, the Bluetooth system of the 2.45 GHzband is used. The Bluetooth system is of a short-distance radiocommunication standard, and uses radio waves of the 2.45 GHz band torealize a radio communication range of about 10 m.

[0033] The personal computer 1 comprises an antenna 1 a fortransmitting/receiving radio waves of the 2.45 GHz band with to/from thecellular phone 2, an LCD 1 b for use as a display monitor, and akeyboard 1 c for inputting data.

[0034]FIG. 3 is a schematic diagram showing a basic configuration of thepersonal computer 1. The personal computer 1 establishes a local linkand communicates with the cellular phone 2 via radio waves. When theradio link is established, the cellular phone 2 can receive theinformation periodically transmitted from the personal computer 1 viaradio waves.

[0035] A host program 101 such as an operating system (OS) andapplication program (APL) and a Bluetooth driver (BUS driver) 102 areresident in a memory on the personal computer 1 (Host side). The BUSdriver 102 controls a host controller 104 as a Bluetooth device itselfvia a USB driver 103. As shown in FIG. 3, the BUS driver 102 of thepresent embodiment includes a station finding processor 201.

[0036] The station finding processor 201 is a software module forinquiring the presence of the cellular phone 2 with a Bluetooth radiomodule mounted thereon in an area within reach of radio waves of thepersonal computer 1.

[0037] The host controller 104 includes a radio communication module 202formed of a link manager controller, and the like. The radiocommunication module 202 carries out physical linking control withrespect to the cellular phone 2.

[0038] For the configuration of the personal computer 1 and cellularphone 2, a hardware configuration and software configuration will beseparately and concretely described.

[0039] Constitution of Personal Computer 1:

[0040]FIG. 4 is a block diagram showing the hardware configuration ofthe personal computer 1. A hardware portion for realizing the presentsystem will mainly be described.

[0041] In the personal computer 1, as a radio module 7 for using radiowaves of the 2.45 GHz band to communicate with the cellular phone 2, aradio antenna 8, radio frequency (RF) section 9, radio baseband section10, memory 11, crystal oscillator 12, AD/DA converter 13, andmicrophone/speaker 14 are mounted. A similar radio module is alsomounted on the cellular phone 2. The radio module 7 is connected to apersonal engine section 15 as a personal computer main unit via a serialinterface 16 such as a USB as described above.

[0042] The radio antenna 8 is a section for transmitting/receiving radiowaves of the 2.45 GHz band to realize the radio communication with thecellular phone 2. During reception, the RF section 9 performs aprocessing of mixing radio waves received via the radio antenna 8 with alocal frequency signal oscillated from the crystal oscillator 12,converting the received signal from the radio antenna 8 to anintermediate frequency (IF) signal, and subsequently demodulating the IFsignal to a digital signal to be handled by the radio baseband section10. The radio baseband section 10 performs a protocol processing. Theradio baseband section 10 converts the signal inputted via the radioantenna 8 and RF section 9 to a data string which can be processed by aCPU.

[0043] During transmission, the reception flow is reversed. That is, theradio baseband section 10 converts transmission data to a signal to behandled by the RF section 9 according to a predetermined protocol, andthe RF section 9 modulates the signals to radio waves of the 2.45 GHzband and transmits radio waves via the radio antenna 8.

[0044] The microphone/speaker 14 is a device for inputting/outputting asound signal, and is connected to the radio baseband section 10 via theAD/DA converter 13.

[0045] The personal computer engine section 15 comprises: a personalcomputer engine (MPU) 17 including a CPU, memory, peripheral controlcircuit, and the like; a light emitting diode (LED) 18 for displaying awarning or the like; a USB interface 19 for connecting a peripheraldevice of the universal serial bus (USB) standard; a liquid crystaldisplay (LCD) 20 for use as a display monitor; a keyboard 21 forinputting data; a personal computer memory card internationalassociation (PCMCIA) interface 22 for mounting a PC card; a hard diskdrive (HDD) 23 in which a history management table and contents to betransmitted are stored as described later; and the like.

[0046]FIG. 5 is a block diagram showing the software configuration ofthe personal computer 1. In a structure shown in FIG. 5, a radioprotocol stack 28 for the radio communication of the 2.45 GHz band ismounted on a personal computer engine section 15 side.

[0047] On the radio module 7 side of the personal computer 1, as shownin FIG. 5, the RF section 9 and radio baseband section 10 are disposedas hardware. A link management protocol (LMP) 23 for controlling theradio link with the radio communication apparatus on a cellular phone 2side via radio waves, and a host control interface (HCI) 24 forperforming a serial interface processing with the personal computerengine section 15 are mounted on the radio baseband section 10.

[0048] Mounted in the personal computer engine section 15 are anoperating system (OS) 25 positively mounted as the personal computer,driver software 26 for controlling various peripheral devices, andvarious applications 27 such as word processor software, tablecalculation software, electronic mail software, and system software forrealizing a remote control function. Additionally, a radio protocolstack 28 for the radio communication of the 2.45 GHz band, an HCI 29 forperforming a serial interface processing with the radio module 7 side,and the like are mounted.

[0049] Constitution of Cellular Phone 2:

[0050]FIG. 6 is a block diagram showing the hardware configuration ofthe cellular phone 2. A hardware section necessary for realizing thepresent system will mainly be described.

[0051] In the cellular phone 2, as a radio module 30 for using radiowaves of the 2.45 GHz band to communicate with the personal computer 1,a radio antenna 31, radio RF section 32, radio baseband section 33,memory 34, and crystal oscillator 35 are mounted. The radio module 30 isconnected to a cellular phone engine 36 via a serial interface 37.

[0052] The radio antenna 31 is a section for transmitting/receiving 2.45GHz band radio waves to realize radio communication with the personalcomputer 1. During reception the radio RF section 32 performs aprocessing of mixing radio waves received via the radio antenna 31 withthe local frequency signal oscillated from the crystal oscillator 35,converting the RF signal to an intermediate frequency signal, andsubsequently demodulating the IF signal to a digital signal to behandled by the radio baseband section 33. The radio baseband section 33performs protocol processing. The radio baseband section 33 converts thesignal inputted via the antenna 31 and RF section 32 to a data stringwhich can be processed by the CPU.

[0053] During transmission, the reception flow is reversed. That is, theradio baseband section 33 converts the transmission data to the signalto be handled by the radio RF section 32 according to the predeterminedprotocol, and the radio RF section 32 modulates the signal to 2.45 GHzband radio waves and transmits radio waves via the radio antenna 31.

[0054] As a common section 47, an AD/DA converter 48, microphone/speaker49, and power source 50 are disposed.

[0055]FIG. 7 is a block diagram showing the software configuration ofthe cellular phone 2. In the structure in FIG. 7, the radio protocolstack 53 of the 2.45 GHz band radio communication is mounted on apersonal computer engine 36 side.

[0056] On the radio module 30 side of the cellular phone 2, as shown inFIG. 7, the RF section 32 and baseband section 33 are disposed ashardware. Moreover, a link management protocol 51 (LMP) for controllingthe radio link with the radio communication apparatus on the personalcomputer 1 side via radio waves, and a host control interface (HCI) 52for performing a serial interface processing with the cellular phoneengine 36 are mounted on the baseband section 33.

[0057] In the cellular phone engine 36, an RF section 41, basebandsection 42, and cellular phone protocol stack 53 are mounted as thecellular phone in a standard manner. Additionally, an application 54including a system software for realizing the remote control function,radio protocol stack 55 for the 2.45 GHz band radio communication, andHCI 56 for performing the serial interface processing with the radiomodule 30 side are mounted.

[0058]FIG. 8 shows one example of a transmission history managementtable stored in the HDD 23 of the personal computer 1 or a receptionhistory management table stored in the memory 46 of the cellular phone2. As shown in FIG. 8, the history management table comprises a userfriendly name 61, Bluetooth address 63, application ID 65, applicationsub IDs 67 and 69, date information 71, and contents pointer 73. In eachrow of the table, data for each transmitted information (application) isregistered in the table of the personal computer 1, and each receivedinformation is registered in the table of the cellular phone 2.

[0059] The Bluetooth address 63 is a unique inherent address of theradio module 30 of the cellular phone 2 as a transmission destination inthe transmission history management table of the personal computer 1.The address is a unique inherent address of the radio module 7 of thepersonal computer 1 as a transmitter in the reception history managementtable of the cellular phone 2. The Bluetooth address 63 is constituted,for example, of a six byte numerals. The user friendly name 61 isinformation corresponding to Bluetooth address information attached insuch a manner that the user can easily recognize the information. Theapplication ID 65 is information indicating a distribution informationcategory. For example, ID 65=“1” denotes music, and ID 65=“2” denotesmovies. The application sub IDs 67 and 69 are information indicating asub category. For example, the application sub ID 67=“1” indicates a subcategory “pop music”, application sub ID 67=“2” indicates a sub category“jazz”, application sub ID 69=“1” indicates a sub category “malesinger”, and application sub ID 69=“2” indicates a sub category “femalesinger”. Additionally, ID may indicates contents instead of thecategory. In this case, one ID is sufficient, and sub ID is unnecessary.The date information 71 indicates a date at which the contents aretransmitted or received. As shown in FIG. 9, the contents pointer 73indicates a location entry address of the HDD 23 or the memory 46 inwhich the respective contents are stored.

[0060]FIG. 10 shows one example of a flowchart of a program for usingthe 2.45 GHz band radio communication to connect the informationproviding server (personal computer 1) to the mobile station (cellularphone 2), and preventing the personal computer 1 from repeatedlytransmitting the same information to the cellular phone 2.

[0061] When the program is started by the personal computer 1, aninquiry about presence/absence of the radio-communicatable cellularphone 2 within reach of radio waves is transmitted via a broadcastrequest in order to find a cellular phone 2. The cellular phone 2 withwhich the radio communication is enabled can be found by a response tothe inquiry transmission (step S1). With the absence of theradio-communicatable cellular phone 2, the processing of step S1 isrepeated at periodic intervals until the radio-communicatable cellularphone 2 appears.

[0062] When the radio-communicatable cellular phone 2 exists, the radiobaseband section 10 is controlled in order to establish a radio linkusing radio communication of the 2.45 GHz band, and the link to the 2.45GHz band radio communication module on the side of the found cellularphone 2 is established (step S3). When there are plural ofradio-communicatable cellular phones 2, plural links are established tothe plural cellular phones 2. The Bluetooth address of the cellularphone 2 can be known by establishing the link.

[0063] It is determined in step S5 whether the Bluetooth address of thecellular phone 2 in the radio communication area agrees with theBluetooth address 63 in the transmission history management table of thepersonal computer 1 (i.e., whether or not the cellular phone's addressis registered in the personal computer 1).

[0064] If it is determined that the Bluetooth address of the cellularphone 2 in the radio communication area is already registered in thetransmission history management table of the personal computer 1, it isdetermined in step S7 whether or not the ID and sub IDs of theapplication to be transmitted next are already registered in thetransmission history management table in the personal computer 1.

[0065] If yes in step S7, it can be seen that the information has beentransmitted from the personal computer 1 to the cellular phone 2.Therefore, no transmission processing is performed. As described later,after the information is transmitted, BT address of the cellular phone 2as the transmission destination, and the ID and sub IDs of thetransmitted application are registered in the transmission historymanagement table. Therefore, when the address of the cellular phone 2,and application ID and sub IDs are registered in the history managementtable, it can be seen that the information has already been transmittedto the cellular phone 2. In this case, after the radio link isdisconnected (step S15), the control processing returns to the firststep S1. This can prevent the same information from being repeatedlytransmitted to the same mobile station.

[0066] On the other hand, when the BT address of the mobile station doesnot exist in the history management table (no in step S5) or even whenthe BT address of the mobile station exists in the history managementtable, the application ID as well as sub IDs to be transmitted next donot exist in the transmission history management table at the rowcorresponding to the registered BT address (no in step S7), it can beseen that the information to be transmitted next has not beentransmitted. Therefore, the personal computer 1 transmits theinformation only to the cellular phone 2 to which the information hasnot been transmitted yet (step S9).

[0067] After the transmission, the history management table is correctedor updated in step S11 if necessary. More specifically, the row of datacorresponding to the information transmitted in step S9 is added to thetransmission history management table. However, the number of rowspossibly stored in the history management table is limited. When the rowcannot be added, the row corresponding to the data having the addressother than the Bluetooth address of the mobile station in the radiocommunication area found in step S1 is deleted. Therefore, the ID of thecellular phone 2 in the radio communication area and ID of theinformation transmitted to the cellular phone 2 are known from thehistory management table.

[0068] The radio link with the cellular phone 2 is disconnected in stepS15. It is determined in step S17 whether there is a request for endingthe program (information providing program) from the user. When there isan ending request, the program is ended. Moreover, when there is noending request, the processing of step S1 is executed.

[0069] Since the data transmitted to the once connected cellular phone 2is managed in this manner in the personal computer 1 (informationproviding server), the same information is prevented from beingrepeatedly transmitted to the same cellular phone 2, and the burden ofthe information providing server is remarkably reduced. Moreover, sincethe same information is prevented from being repeatedly received even inthe cellular phone 2, power necessary for a reception processing can beremarkably suppressed.

[0070] According to the present embodiment, there is provided a mobilestation which can communicate with an information providing server byradio, the mobile station comprising a radio link establishing sectionwhich establishes a radio link with the information providing server; aninformation receiving section which receives information from theinformation providing server after establishing the radio link; ahistory management table in which at least identification information ofthe information providing server having already received the informationis stored; means for referring to the identification information in thehistory management table, and determining whether the informationproviding server is to transmit the same information as the alreadyreceived information; and means for preventing the information frombeing received from the information providing server when theinformation providing server transmits the same information as thealready received information.

[0071] The transmitted information is stored in the mobile station, andthe information transmitted from the same information providing serveris prevented from being received. The contents of the stored informationcan be checked at a time convenient for the user.

[0072] Moreover, after a series of information is transmitted from theinformation providing server to the mobile station while the mobilestation is connected to the information providing server, the mobilestation is disconnected from the information providing server. Even inthe area in which the mobile station can communicate with theinformation providing server, the information providing server does nottransmit a request for connection to the mobile terminal, and the mobileterminal does not receive the connection request from the informationproviding server.

[0073]FIG. 11 shows one example of a flowchart of a program for usingthe 2.45 GHz band radio communication to connect the cellular phone 2 tothe personal computer 1, and preventing the cellular phone 2 fromrepeatedly receiving the same information transmitted from the personalcomputer 1.

[0074] When the program is started by the cellular phone 2, it isdetermined whether there is a radio link request from another 2.45 GHzband radio communication apparatus (personal computer 1 in this example)(step S21). When there is no radio link request, the processing of stepS21 is repeated at a periodic interval until the link request isreceived.

[0075] When there is a radio link request, the baseband section 33 iscontrolled in order to establish the radio link using the 2.45 GHz bandradio communication, and the link to the 2.45 GHz band radiocommunication apparatus 1 is established (step S23).

[0076] It is determined in step S25 whether the Bluetooth address of thelinked personal computer 1 agrees with the Bluetooth address 63 in thereception history management table of the cellular phone 2 (i.e.,whether the address is already registered in the table).

[0077] If it is determined that the Bluetooth address of the personalcomputer 1 is already registered in the reception history managementtable, it is determined in step S27 whether or not the ID of theapplication to be transmitted by the personal computer 1 is alreadyregistered in the reception history management table in the cellularphone 2.

[0078] If yes in step S27, it can be seen that the information hasalready been received, and therefore no reception processing isperformed. As described later, after the information is received, the BTaddress of the personal computer 1 as the transmitter of theinformation, and the ID and sub IDs of the received application areregistered in the reception history management table. Therefore, whenthe BT address of the personal computer 1, and application ID and subIDs are registered in the reception history management table, it can beseen that the information has already been transmitted from the personalcomputer 1. In this case, the radio link is disconnected (step S37), andthe control processing returns to the first step S21. This can preventthe same information from being repeatedly received from the samepersonal computer 1.

[0079] On the other hand, when the BT address of the personal computer 1does not exist in the reception history management table (no in stepS25), or even when the BT address of the mobile station exists in thehistory management table, the application ID and sub IDs to be receivednext do not exist in the history management table at the rowcorresponding to the registered BT address (no in step S27), it can beseen that the information to be transmitted from the personal computer 1has not been received yet. Therefore, the reception processing iscarried out (step S29).

[0080] After the reception, the received information is stored in thememory 46 in step S31. However, when the capacity of the memory 46 isfull, the oldest data is deleted. In step S31, the reception historymanagement table is corrected or updated if necessary. If data isdeleted from the memory 46 in step S31, the row of data corresponding tothe deleted information is also deleted from the reception historymanagement table. Then, a row of data corresponding to the storedinformation is added to the history management table. If the tablecapacity is full, the row of data corresponding to the oldest receiveddata is deleted. Thereby, a history of received data in the past is leftin the reception history management table.

[0081] The radio link with the personal computer 1 is disconnected instep S37. It is determined in step S39 whether there is a request forending the program (information receiving program) from the user. Whenthere is an ending request, the program is ended. Moreover, when thereis no ending request, the processing of step S21 is executed.

[0082] Since the once received data is managed on the cellular phoneside in this manner and the same information transmitted from theinformation providing server is prevented from being received, powerconsumption necessary for the reception of the cellular phone can besuppressed. Furthermore, since the received information is stored, thereceived contents can be checked at the user's desired timing.

[0083] The first embodiment can be modified as follows. The distributioninformation may be of one type. In this case, the application ID and subIDs are unnecessary in the history management table, step S7 ofmonitoring the application ID and sub IDs is unnecessary in thetransmission control flow (FIG. 10), and step S27 of monitoring theapplication ID and sub IDs is unnecessary in the reception control flow(FIG. 11). The transmission/reception may be controlled only bydetermining whether the BT address has been registered. Furthermore,even when the distribution information is of a plurality of types, thetransmission/reception processing may be performed by monitoring onlythe application ID and sub IDs without considering the presence/absenceof the registered BT address, and step S5 or S25 may be omitted.

[0084] As described above, according to the first embodiment, on thetransmission side the transmission destination of the information to bedistributed is managed and redundant transmission is prevented, and alsoon the reception side the received information is managed and redundantreception is prevented. Therefore, the same information is preventedfrom being redundantly received by the same mobile station, and thepower consumption for reception in the mobile station can be suppressed.Moreover, when the received information is stored in the memory of themobile station, the information can be browsed from the arbitraryposition of the information.

[0085] In the first embodiment, the transmitted and received informationare managed on both the transmission and reception sides. If it isunnecessary to transmit or receive, the radio link is disconnected fromeither apparatus, and no transmission/reception processing is performed,but such control function may be disposed only on the reception side.

[0086] In the first embodiment, since the individual information istransmitted to seven cellular phones at maximum, the transmissionprocessing is controlled for each cellular phone. Transmission of thesame information to the seven cellular phones at maximum will bedescribed as a second embodiment. Transmission of the same informationto a plurality of cellular phones is sometimes called broadcast. Forexample, repeated transmission of a train timetable and fare table to anunspecified number of cellular phones in a train station is considered.In this case, in view of the storage capacity or the like, it isdifficult to store the connection history management table with respectto an unspecified number of cellular phones. Therefore, a personalcomputer as the information providing server repeatedly transmits thesame information to seven cellular phones at maximum in the radiocommunication area of the personal computer without storing theconnection history. However, when the same information is prevented frombeing repeatedly received on the cellular phone side, the effect similarto that of the first embodiment can be produced.

[0087]FIG. 12 is a flowchart showing a processing on an informationproviding server side, in which the information providing serverbroadcasts/transmits contents.

[0088] In FIG. 12, when the program of the information providing serveris started, an inquiry about the presence/absence of aradio-communicatable mobile station within reach of radio waves istransmitted via the broadcast request in order to find theradio-communicatable station. The station to be communicated can befound by the response (step S41) from the station. With the absence ofthe radio-communicatable station, the processing of step S41 is repeatedat a periodic interval until the radio-communicatable cellular phoneappears. When the radio-communicatable station exists, the radiobaseband section 10 of the personal computer is controlled in order toestablish a radio link using the 2.45 GHz band radio communication, andthe radio link to the cellular phone is established (step S43). Afterthe radio link is established, the information providing servertransmits the information to the cellular phone (step S45).Subsequently, the radio link with the cellular phone is disconnected(step S47). It is finally determined whether there is a program endingrequest from the user (step S49). When there is the ending request, theprogram is ended. Moreover, when there is no ending request, theprocessing of step S41 is repeated.

[0089] According to the second embodiment, the processing on thecellular phone side is similar to the processing of the flowchart shownin FIG. 11.

[0090] In the above embodiments, there are a multiplicity of types ofdistribution information, and the information cannot be distinguishedwithout using ID. However, contents to be transmitted are an applicationsuch that information can be distinguished only by date of theinformation, such as stock price information. In this case, theapplication ID and application sub IDs can be deleted from the historymanagement table in FIG. 8. The data of the information indicates dateof creating the information. If the date of the information to betransmitted/received is the same as that registered in the historymanagement table, it is not necessary to transmit/receive theinformation.

[0091]FIG. 13 is a diagram showing this history management table. Asshown in FIG. 13, the history management table is constituted of theuser friendly name, Bluetooth address, date information, and contentspointer.

[0092]FIG. 14 showings another embodiment for preventing the informationproviding server from repeatedly transmitting the same information tothe mobile station. In the embodiment, the radio link is established,the information including information indicating the contents ofinformation already received by the mobile station (application ID andsub ID, and the like) is transmitted to the information providing serverfrom the mobile station. Thereby, the information providing server cantransmit contents other than the information indicated by thetransmitted information to the mobile station. In this case, theinformation providing server does not need to have any historymanagement table. Therefore, as in the first and second embodiments, thesame information can be prevented from being repeatedly transmitted tothe mobile station.

[0093]FIG. 15 shows a modification example of the embodiment shown inFIG. 14. The information transmitted to the information providing serverfrom the mobile station is constituted of the Bluetooth address and dateinformation. The information providing server refers to the dateinformation transmitted from the mobile station, and can transmit anyinformation newer than the date information. In this case, the repeatedtransmission of the same information to the cellular phone can beprevented.

[0094] The present invention is not limited to the above embodiments.Devices other than the personal computer and the cellular phone can beused as the information providing server and mobile station. Theinformation distributed to the mobile stations is not limited to theabove example. The radio link is not limited to the 2.45 GHz band radiocommunication of Bluetooth.

INDUSTRIAL APPLICABILITY

[0095] According to the present invention, a radio communicationapparatus comprises a reception history table configured to storeinformation-identification identifying information which has beenreceived; and a controller configured to prevent information from beingreceived of which information-identification is stored in said receptionhistory table.

[0096] According to the present invention, a radio communicationapparatus comprises a transmission history table configured to storeinformation-identification identifying information which has beentransmitted; and a controller configured to prevent information frombeing transmitted of which information-identification is stored in saidtransmission history table.

[0097] The information repeatedly transmitted from the informationproviding server is prevented from being repeatedly received. Therefore,the power consumption necessary for reception can be reduced.

1. A radio communication apparatus comprising: a reception history tableconfigured to store information-identification identifying receivedinformation; and a controller configured to prevent information frombeing received of which information-identification is stored in saidreception history table.
 2. The apparatus according to claim 1, whereinsaid reception history table stores apparatus-identification identifyingthe other apparatus which transmits information to be received andcategory-identification identifying a category of the information to bereceived; and said controller comprises: a radio link connection unitconfigured to establish a radio link to the other apparatus; a receiverconfigured to receive the apparatus-identification of the otherapparatus and the information-identification of the information to bereceived; a comparator configured to determine whether the receivedapparatus-identification and received information-identification arestored in said reception history table; and a radio link disconnectionunit configured to disconnect the radio link if it is determined thatthe received apparatus-identification and receivedinformation-identification are stored in said reception history table.3. The apparatus according to claim 2, wherein said controller furthercomprises: an information receiver configured to receive the informationfrom the other apparatus if it is determined that the receivedapparatus-identification and received information-identification are notstored in said reception history table; and a table update unitconfigured to register the received apparatus-identification andreceived information-identification in said reception history table. 4.The apparatus according to claim 1, wherein said reception history tablestores date-information of the received information; and said controllercomprises: a radio link connection unit configured to establish a radiolink to the other apparatus; a receiver configured to receive thedate-information of the information to be transmitted by the otherapparatus; a comparator configured to compare the receiveddate-information and the date-information stored in said receptionhistory table; and a radio link disconnection unit configured todisconnect the radio link if the received date-information equals to thedate-information stored in said reception history table.
 5. Theapparatus according to claim 4, wherein said controller furthercomprises: an information receiver configured to receive the informationfrom the other apparatus if the received date-information does not equalto the date-information stored in said reception history table; and atable update unit configured to register the date-information of thereceived information in said reception history table.
 6. A radiocommunication method comprising: establishing a radio link to anotherapparatus; receiving information-identification identifying informationto be received; determining whether the receivedinformation-identification is stored in a reception history table whichstores the information-identification identifying received information;and disconnecting the radio link if it is determined that the receivedinformation-identification is stored in said reception history table. 7.The method according to claim 6, further comprising: receiving theinformation from the other apparatus if it is determined that thereceived information-identification is not stored in said receptionhistory table; and registering the information-identification of thereceived information in said reception history table.
 8. The methodaccording to claim 6, wherein said information-identification comprisesapparatus-identification identifying the other apparatus andcategory-identification identifying a category of information.
 9. Themethod according to claim 6, wherein said information-identificationcomprises date-information.
 10. A radio communication apparatuscomprising: a transmission history table configured to storeinformation-identification identifying transmitted information; and acontroller configured to prevent information from being transmitted ofwhich information-identification is stored in said transmission historytable.
 11. The apparatus according to claim 10, wherein saidtransmission history table stores apparatus-identification identifyingthe other apparatus to which the information was transmitted andcategory-identification identifying a category of the transmittedinformation; and said controller comprises: a radio link connection unitconfigured to establish a radio link to the other apparatus; a receiverconfigured to receive the apparatus-identification of the otherapparatus and the category-identification identifying a category of theinformation which was received by the other apparatus; a comparatorconfigured to determine whether the received apparatus-identificationand the category-identification are stored in said transmission historytable; and a radio link disconnection unit configured to disconnect theradio link if it is determined that the receivedapparatus-identification and received category-identification are storedin said transmission history table.
 12. The apparatus according to claim11, wherein said controller further comprises: an informationtransmitter configured to transmit the information to the otherapparatus if it is determined that the received apparatus-identificationand received category-identification are not stored in said transmissionhistory table; and a table update unit configured to register theapparatus-identification of the other apparatus andcategory-identification of the transmitted information in saidtransmission history table.
 13. A radio communication method comprising:establishing a radio link to another apparatus; receivinginformation-identification identifying information which was received bythe other apparatus; determining whether the receivedinformation-identification is stored in a transmission history tablewhich stores the information-identification identifying informationwhich was transmitted to the other apparatus; and disconnecting theradio link if it is determined that the receivedinformation-identification is stored in said transmission history table.14. The method according to claim 13, further comprising: transmittingthe information to the other apparatus if it is determined that thereceived information-identification is not stored in said transmissionhistory table; and registering the information-identification of thetransmitted information in said transmission history table.
 15. Themethod according to claim 13, wherein said information-identificationcomprises apparatus-identification identifying the other apparatus andcategory-identification identifying a category of information.
 16. Aradio communication system comprising: transmitter units, each of whichconfigured to transmit information; and receiver units, each of whichconfigured to receive the information transmitted from one of saidtransmitter units, wherein at least one of said transmitter units andsaid receiver units comprise: an information management table configuredto store information-identification identifying information which hasbeen transmitted from one of said transmitter units to one of saidreceiver units, transmitter-identification identifying one of thetransmitters which has transmitted the information, andreceiver-identification identifying one of the receiver which hasreceived the information; and a controller configured to prevent thesame information from being received by the same receiver.
 17. Thesystem according to claim 16, wherein said transmitter units and saidreceiver units are connected by a radio link based on Bluetoothprotocol.